The effect of COVID-19 vaccine to the Omicron variant in children and adolescents: a systematic review and meta-analysis.

Background: Omicron (B.1.1.529), a variant of SARS-CoV-2, has emerged as a dominant strain in COVID-19 pandemic. This development has raised concerns about the effectiveness of vaccination to Omicron, particularly in the context of children and adolescents. Our study evaluated the efficacy of different COVID-19 vaccination regimens in children and adolescents during the Omicron epidemic phase. Methods: We searched PubMed, Cochrane, Web of Science, and Embase electronic databases for studies published through March 2023 on the association between COVID-19 vaccination and vaccine effectiveness (VE) against SARS-CoV-2 infection in children and adolescents at the Omicron variant period. The effectiveness outcomes included mild COVID-19 and severe COVID-19. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and was prospectively registered in PROSPERO (CRD42023390481). Results: A total of 33 studies involving 16,532,536 children were included in the analysis. First, in children and adolescents aged 0-19 years, the overall VE of the COVID-19 vaccine is 45% (95% confidence interval [CI]: 40 to 50%). Subgroup analysis of VE during Omicron epidemic phase for different dosage regimens demonstrated that the VE was 50% (95% CI: 44 to 55%) for the 2-dose vaccination and 61% (95% CI: 45 to 73%) for the booster vaccination. Upon further analysis of different effectiveness outcomes during the 2-dose vaccination showed that the VE was 41% (95% CI: 35 to 47%) against mild COVID-19 and 71% (95% CI: 60 to 79%) against severe COVID-19. In addition, VE exhibited a gradual decrease over time, with the significant decline in the efficacy of Omicron for infection before and after 90 days following the 2-dose vaccination, registering 54% (95% CI: 48 to 59%) and 34% (95% CI: 21 to 56%), respectively. Conclusion: During the Omicron variant epidemic, the vaccine provided protection against SARS-CoV-2 infection in children and adolescents aged 0-19 years. Two doses of vaccination can provide effective protection severe COVID-19, with booster vaccination additionally enhancing VE.

A highly sensitive and selective fluorescent biosensor for breast cancer derived exosomes using click reaction of azide-CD63 aptamer and alkyne-polymer dots.

Exosomes have gained recognition as valuable reservoirs of biomarkers, holding immense potential for early cancer detection. Consequently, there is a pressing need for the development of an economical and highly sensitive exosome detection methodology. In this work, we present a fluorescence method for breast cancer-derived exosome detection based on Cu-triggered click reaction of azide-modified CD63 aptamer and alkyne functionalized Pdots. The detection threshold for the exosomes obtained from the breast cancer serum was determined to be 6.09 × 107 particles per µL, while the measurable range spanned from 6.50 × 107 to 1.30 × 109 particles per µL. The employed methodology achieved notable success in accurately distinguishing breast cancer patients from healthy individuals through serum analysis. The application of this method showcases the significant potential for early exosome analysis in the clinical diagnosis of breast cancer patients.

An amino-rich polymer-coated magnetic nanomaterial for ultra-rapid separation of phosphorylated peptides in the serum of Parkinson's disease patients.

The elucidation of disease pathogenesis can be achieved by analyzing the low-abundance phosphopeptides in organisms. Herein, we developed a novel and easy-to-prepare polymer-coated nanomaterial. By improving the hydrophilicity and spatial conformation of the material, we effectively enhanced the adsorption of phosphopeptides and demonstrated excellent enrichment properties. The material was able to successfully enrich the phosphopeptides in only 1 min. Meanwhile, the material has high selectivity (1:2000), good loading capacity (100 µg/mg), excellent sensitivity (0.5 fmol), and great acid and alkali resistance. In addition, the material was applied to real samples, and 70 phosphopeptides were enriched from the serum of Parkinson's disease (PD) patients and 67 phosphopeptides were enriched from the serum of normal controls. Sequences Logo showed that PD is probably associated with threonine, glutamate, serine, and glutamine. Finally, gene ontology (GO) analysis was performed on phosphopeptides enriched in PD patients' serum. The results showed that PD patients expressed abnormal expression of the cholesterol metabolic process and cell-matrix adhesion in the biological process (BP), endoplasmic reticulum and lipoprotein in the cellular component (CC), and heparin-binding, lipid-binding, and receptor-binding in the molecular function (MF) as compared with normal individuals. All the experiments indicate that the nanomaterials have great potential in proteomics studies.

Chitin whisker/chitosan liquid crystal hydrogel assisted scaffolds with bone-like ECM microenvironment for bone regeneration.

Natural bone exhibits a complex anisotropic and micro-nano hierarchical structure, more importantly, bone extracellular matrix (ECM) presents liquid crystal (LC) phase and viscoelastic characteristics, providing a unique microenvironment for guiding cell behavior and regulating osteogenesis. However, in bone tissue engineering scaffolds, the construction of bone-like ECM microenvironment with exquisite microstructure is still a great challenge. Here, we developed a novel polysaccharide LC hydrogel supported 3D printed poly(l-lactide) (PLLA) scaffold with bone-like ECM microenvironment and micro-nano aligned structure. First, we prepared a chitin whisker/chitosan polysaccharide LC precursor, and then infuse it into the pores of 3D printed PLLA scaffold, which was previously surface modified with a polydopamine layer. Next, the LC precursor was chemical cross-linked by genipin to form a hydrogel network with bone-like ECM viscoelasticity and LC phase in the scaffold. Subsequently, we performed directional freeze-casting on the composite scaffold to create oriented channels in the LC hydrogel. Finally, we soaked the composite scaffold in phytic acid to further physical cross-link the LC hydrogel through electrostatic interactions and impart antibacterial effects to the scaffold. The resultant biomimetic scaffold displays osteogenic activity, vascularization ability and antibacterial effect, and is expected to be a promising candidate for bone repair.

The regulation of the pedunculopontine tegmental nucleus in sleep-wake states.

The pedunculopontine tegmental nucleus (PPTg) plays a vital role in sleep/wake states. There are three main kinds of heterogeneous neurons involved: cholinergic, glutamatergic, and gamma-aminobutyric acidergic (GABAergic) neurons. However, the precise roles of cholinergic, glutamatergic and GABAergic PPTg cell groups in regulating sleep-wake are unknown. Recent work suggests that the cholinergic, glutamatergic, and GABAergic neurons of the PPTg may activate the main arousal-promoting nucleus, thus exerting their wakefulness effects. We review the related projection pathways and functions of various neurons of the PPTg, especially the mechanisms of the PPTg in sleep-wake, thus providing new perspectives for research of sleep-wake mechanisms.

Improving Magnetic Resonance Imaging and Chemodynamic Therapy Properties via Tuning the Fe(II)/Fe(III) Ratio in Hydrophilic Single-Atom Nanobowls.

We developed an intrinsic hydrophilic single-atom iron nanobowl (Fe-SANB) for magnetic resonance imaging (MRI)-guided tumor microenvironment-triggered cancer therapy. Benefiting from the sufficient exposure of Fe single atoms and the intrinsic hydrophilicity of the bowl-shaped structure, the Fe-SANBs exhibited a superior performance for T1-weighted MRI with an r1 value of 11.48 mM-1 s-1, which is 3-fold higher than that of the commercial Gd-DTPA (r1 = 3.72 mM-1 s-1). After further coembedding Gd single atoms in the nanobowls, the r1 value can be greatly improved to 19.54 mM-1 s-1. In tumor microenvironment (TME), the Fe-SANBs can trigger pH-induced Fenton-like activity to generate highly toxic hydroxyl radicals for high-efficiency chemodynamic therapy (CDT). Both the MRI and CDT efficiency of these nanobowls can be optimized by tuning the ratio of Fe(II)/Fe(III) in the Fe-SANBs via controlling the calcination temperature. Furthermore, the generation of •OH at the tumor site can be accelerated via the photothermal effect of Fe-SANBs, thus promoting CDT efficacy. Both in vitro and in vivo results confirmed that our nanoplatform exhibited high T1-weighted MRI contrast, robust biocompatibility, and satisfactory tumor treatment, providing a potential nanoplatform for MRI-guided TME-triggered precise cancer therapy.

Using self-reported sexual positioning as an indicator for rectal chlamydia and gonorrhea screening among men who have sex with men in China: a missed opportunity.

BACKGROUND: Rectal chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections among men who have sex with men (MSM) are escalating public health concerns. This study aimed to explore (1) the reliability of self-reported sexual positioning as an indicator for rectal CT and NG screening; and (2) factors associated with rectal CT and NG infections in Shenzhen, China. METHODS: A cross-sectional study was conducted in two settings in Shenzhen, China, from 1st April 2021 to 31st March 2022. Data on sociodemographic characteristics, sexual behaviors, and basic CT knowledge was collected. Urine and self-collected rectal swabs were collected for CT and NG testing. RESULTS: In total, 195 MSM participated in the study, and 5.1% tested positive for urogenital CT, 29.2% for rectal CT, 1.0% for urogenital NG, and 8.2% for rectal NG. Among those who reported exclusively insertive anal sex, 69.2% of CT infections and 85.7% of NG infections would have remained undetected with urine testing alone. Risk factors for rectal CT infection included engaging in both insertive and receptive anal sex, with a significant association found for co-infection with rectal NG. CONCLUSIONS: Self-reported sexual positioning was found to be an unreliable indicator for CT and NG screening, as a substantial proportion of infections would have remained undetected. The findings suggest that CT and NG screening in China should be offered to all MSM regardless of self-reported sexual positioning, and that the dual CT/NG testing is recommended.

Highly sensitive quantitative detection of glycans on exosomes in renal disease serums using fluorescence signal amplification strategies.

Exosomal glycoproteins play a significant role in many physiological and pathological processes. However, the detection of exosome surface glycans is currently challenged by the complexity of biological samples or the sensitivity of the methods. Herein, we prepared a novel fluorescent probe of biotin-functionalized nanocrystals (denoted as CdTe@cys-biotin) and applied it for the first time for the detection of the expression of exosomal surface glycans using a fluorescence amplification strategy. First, the dual affinity of TiO2 and CD63 aptamers of Fe3O4@TiO2-CD63 was utilized to rapidly and efficiently capture exosomes within 25 min. In this design, interference from other vesicles and soluble impurities can be avoided due to the dual recognition strategy. The chemical oxidation of NaIO4 oxidized the hydroxyl sites of exosomal surface glycans to aldehydes, which were then labeled with aniline-catalyzed biotin hydrazide. Using the high affinity between streptavidin and biotin, streptavidin-FITC and probes were successively anchored to the glycans on the exosomes. The fluorescent probe achieved the dual function of specific recognition and fluorescent labeling by modifying biotin on the surface of nanocrystals. This method showed excellent specificity and sensitivity for exosomes at concentrations ranging from 3.30 × 102 to 3.30 × 106 particles/mL, with a detection limit of 121.48 particles/mL. The fluorescent probe not only quantified exosomal surface glycans but also distinguished with high accuracy between serum exosomes from normal individuals and patients with kidney disease. In general, this method provides a powerful platform for sensitive detection of exosomes in cancer diagnosis.

Flexible Hybrid Wearable Sensors for Pressure and Thermal Sensing Based on a Double-Network Hydrogel.

Flexible sensors have attracted great attention due to their wide applications in various fields such as motion monitoring and medical health. It is reasonable to develop a sensor with good flexibility, sensitivity, and biocompatibility for wearable device applications. In this study, a double-network hydrogel was obtained by blending poly(vinyl alcohol) (PVA) with poly(ethylene glycol) diacrylate (PEGDA), which combines the flexibility of the PVA network and the fast photocuring ability of PEGDA. Subsequently, polydopamine-coated carbon nanotubes were used as conductive fillers of the PVA-PEG hydrogel matrix to prepare a flexible sensor that exhibits an effective mechanical response and significant stability in mechanics and conductivity. More importantly, the resistance of the sensor is very sensitive to pressure and thermal changes due to the optimized conductive network in the hydrogel. A motion monitoring test showed that the flexible sensor not only responds quickly to the motion of different joints but also keeps the output signal stable after many cycles. In addition, the excellent cell affinity of the hybrid hydrogel also encourages its application in health monitoring and motion sensors.

Monitoring the Relationship between Social Network Status and Influenza Based on Social Media Data.

BACKGROUND: This article aims to analyze the relationship between user characteristics on social networks and influenza. METHODS: Three specific research questions are investigated: (1) we classify Weibo updates to recognize influenza-related information based on machine learning algorithms and propose a quantitative model for influenza susceptibility in social networks; (2) we adopt in-degree indicator from complex networks theory as social media status to verify its coefficient correlation with influenza susceptibility; (3) we also apply the LDA topic model to explore users' physical condition from Weibo to further calculate its coefficient correlation with influenza susceptibility. From the perspective of social networking status, we analyze and extract influenza-related information from social media, with many advantages including efficiency, low cost, and real time. RESULTS: We find a moderate negative correlation between the susceptibility of users to influenza and social network status, while there is a significant positive correlation between physical condition and susceptibility to influenza. CONCLUSIONS: Our findings reveal the laws behind the phenomenon of online disease transmission, and providing important evidence for analyzing, predicting, and preventing disease transmission. Also, this study provides theoretical and methodological underpinnings for further exploration and measurement of more factors associated with infection control and public health from social networks.

Ti4+ functionalized ß-cyclodextrin covalent organic framework as a new immobilized metal ion affinity chromatography platform for selective capture of phosphorylated peptides and exosomes.

A Ti4+ functionalized ß-cyclodextrin covalent organic framework nanoparticle (named as ß-CD-COF@Ti4+) was synthesized using a one-pot method successfully realizing the enrichment of phosphorylated peptides and exosomes based on the immobilized metal ion affinity chromatography strategy. The functionalized ß-CD-COF@Ti4+ exhibited superior performance on the enrichment of phosphopeptides, including high selectivity (1:1000), low detection limit (0.5 fmol), and loading capacity for phosphopeptides (100 mg·g-1). After treatment with ß-CD-COF@Ti4+, 9 phosphopeptides from defatted milk, 29 phosphopeptides related to 23 phosphoproteins from normal group serum, and 24 phosphopeptides related to 22 phosphoproteins from the serum of uremia patients were captured. Through the analysis of Gene Ontology, the captured phosphoprotein is closely related to kidney disease, including lipoprotein metabolism, very-low-density lipoprotein particle, high-density lipoprotein particle, and lipid binding activity process. Furthermore, western blot verification showed that this nanoparticle could successfully capture exosomes from human serum. This study demonstrates great prospects for the enrichment of phosphopeptides and exosomes from actual bio-samples.

Astrocytes Are Involved in the Effects of Ketamine on Synaptic Transmission in Rat Primary Somatosensory Cortex.

BACKGROUND: Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, is widely used as a general anaesthetic. However, the mechanisms of analgesic/anaesthetic effects induced by ketamine are only partially understood. Previously, studies have demonstrated that various general anaesthetics affect the primary somatosensory cortex (S1), a potential target of general anaesthetics in the central nervous system. However, it is unknown if astrocyte activities affect ketamine's effects on information transmission in S1 pyramidal neurons. METHODS: The whole-cell patch-clamp technique was employed to study the role of astrocytes in ketamine-induced anaesthetic actions. The whole-cell patch-clamp method was used to record the spontaneous postsynaptic currents (SPSCs) of rat S1 pyramidal neurons. We used the glia-selective inhibitor of the aconitase enzyme fluorocitrate (FC), to test if astrocyte activities alter the effects of ketamine on S1 pyramidal neurons. RESULTS: Ketamine lowered the SPSCs of rat S1 pyramidal neurons in a concentration-dependent manner at clinically relevant doses. The concentration-effect curve revealed that ketamine had an EC50 value of 462.1 M for suppressing SPSCs. In rat S1 pyramidal neurons, the glia-selective metabolic inhibitor fluorocitrate (FC), which inhibits the aconitase enzyme, lowered the amplitude and frequency of SPSCs. The inhibitory impact of ketamine on the amplitude and frequency of SPSCs was significantly amplified in the presence of FC. CONCLUSIONS: Astrocytes impact the effects of ketamine on pre- and postsynaptic components and play a role in synaptic transmission.

Revealing the Adsorption Mechanisms of Methanol on Lithium-Doped Porous Carbon through Experimental and Theoretical Calculations.

Previous reports have shown that it is difficult to improve the methanol adsorption performance of nitrogen and oxygen groups due to their low polarity. Here, we first prepared porous carbon with a high specific surface area and large pore volume using benzimidazole as a carbon precursor and KOH as an activating agent. Then, we improved the surface polarity of the porous carbon by doping with Lithium (Li) to enhance the methanol adsorption performance. The results showed that the methanol adsorption capacity of Li-doped porous carbon reached 35.4 mmol g-1, which increased by 57% compared to undoped porous carbon. Molecular simulation results showed that Li doping not only improved the methanol adsorption performance at low pressure, but also at relatively high pressure. This is mainly because Li-modified porous carbon has higher surface polarity than nitrogen and oxygen-modified surfaces, which can generate stronger electrostatic interactions. Furthermore, through density functional theory (DFT) calculations, we determined the adsorption energy, adsorption distance, and charge transfer between Li atom and methanol. Our results demonstrate that Li doping enhances the adsorption energy, reduces the adsorption distance, and increases the charge transfer in porous carbon. The mechanism of methanol adsorption by Li groups was revealed through experimental and theoretical calculations, providing a theoretical basis for the design and preparation of methanol adsorbents.

Understanding the valuation of paediatric health-related quality of life: a qualitative study protocol.

INTRODUCTION: There is evidence from previous studies that adults value paediatric health-related quality of life (HRQoL) and adult HRQoL differently. Less is known about how adolescents value paediatric HRQoL and whether their valuation and decision-making processes differ from those of adults. Discrete choice experiments (DCEs) are widely used to develop value sets for measures of HRQoL, but there is still much to understand about whether and how the methods choices in the implementation of DCE valuation tasks, such as format, presentation and perspective, affect the decision-making process of participants. This paper describes the protocol for a qualitative study that aims to explore the decision-making process of adults and adolescents when completing DCE valuation tasks. The study will also explore the impact of methodological choices in the design of DCE studies (including decisions about format and presentation) on participants' thinking process. METHODS AND ANALYSIS: An interview protocol has been developed using DCE valuation tasks. Interviews will be conducted online via Zoom with both an adolescent and adult sample. In the interview, the participant will be asked to go through some DCE valuation tasks while 'thinking aloud'. After completion of the survey, participants will then be asked some predetermined questions in relation to various aspects of the DCE tasks. Interviews will be recorded and transcribed and analysed using a thematic analysis approach. ETHICS AND DISSEMINATION: Ethics approval for this study has been received for the adult sample (UTS ETH20-9632) as well as the youth sample (UTS ETH22-6970) from the University of Technology Sydney Human Research Ethics Committee. Results from this study will inform the methods to be used in development of value sets for use in the health technology assessment of paediatric interventions and treatments. Findings from this study will also be disseminated through national/international conferences and peer-reviewed journals.

Modulating of Bouligand Structure and Chirality Constructed Bionically Based on the Self-Assembly of Chitin Whiskers.

Chitin can self-assemble into a liquid crystal phase with supramolecular chirality and Bouligand structure, which is widely found in the exoskeletons of arthropods. However, bionically replicating this structure via the self-assembly of chitin whiskers (CHWs) is still a challenge. Here, the effects of several internal and external parameters on the self-assembly of CHWs were revealed based on liquid crystal phase, chirality, Bouligand structure, and rheological properties. The formation of chiral liquid crystal phase and Bouligand structure largely depends on the concentration of CHWs and, meanwhile, is affected by the aspect ratio and zeta potential of CHWs and the self-assembly time. Impressively, introducing electrolytes and changing pH significantly affect the thickness of the electrical double layer, thereby also affecting the self-assembly of CHWs. This study offers a comprehensive understanding of CHWs' self-assembly process, which is beneficial for the bionic design of new nature-inspired functional materials with chiral characteristic and Bouligand structure.

Self-assembly of hydrazide-linked porous organic polymers rich in titanium for efficient enrichment of glycopeptides and phosphopeptides from human serum.

In this work, titanium-rich hydrazide-linked porous organic polymers (hydrazide-POPs-Ti4+) were synthesized using hydrazine, 2,3-dihydroxyterephthalaldehyde (DHTA) and trimethyl 1,3,5-benzenetricarboxylate (TP) as the ligands. Hydrazide-POPs-Ti4+ combined with HILIC and IMAC can be used for simultaneous enrichment of glycopeptides and phosphopeptides. The detection limit of this protocol is 0.1 fmol µL-1 for glycopeptides and 0.005 fmol µL-1 for phosphopeptides, and the selectivities are 1 : 1000 and 1 : 2000 for glycopeptides and phosphopeptides, respectively. For practical bio-sample analysis, 201 glycopeptides associated with 129 glycoproteins and 26 phosphopeptides associated with 21 phosphoproteins were selectively captured from healthy human serum, and 186 glycopeptides associated with 117 glycoproteins and 60 phosphopeptides associated with 50 phosphoproteins were enriched in the serum of breast cancer patients. Gene Ontology analysis indicated that the identified glycoproteins and phosphoproteins were linked to breast cancer, including the binding of complement component C1q and low-density lipoprotein particles, protein oxidation and complement activation, suggesting that these connected pathways are probably engaged in the disease pathology of breast cancer.

Facile preparation of porphyrin-based porous organic polymers for specific enrichment and isolation of phosphopeptides and phosphorylated exosomes.

Exosomes, which can be used to investigate various disease processes, are novel disease markers that have been extensively studied in recent years. In this work, zirconium-rich porphyrin-based porous organic polymers (Imi-Pops-Zr) were synthesized by a facile and low-cost strategy for specific enrichment and isolation of phosphorylated peptides and exosomes. The proposed material demonstrates a low detection limit (0.5 fmol), a high selectivity (bovine serum albumin (BSA): ß-casein = 1000:1), and a loading capability of 100 mg/g for phosphopeptides. For complex practical samples, after enrichment with Imi-Pops-Zr, 4 characteristic phosphopeptides from human serum, 20 and 12 phosphopeptides from human saliva and defatted milk were detected, respectively. Besides, 74 phosphorylated peptides with 67 phosphorylation sites belonging to 61 phosphoproteins and 67 phosphorylated peptides with 63 phosphorylation sites belonging to 65 phosphoproteins were detected from the serum of normal controls and uremic patients, respectively. Biological processes, cellular components and molecular functions revealed that interleukin-6, tumor necrosis factor, high density lipoprotein and proteases binding may be associated with uremia. Furthermore, Imi-Pops-Zr was successfully used to enrich and isolate exosomes from human serum. The experimental results show that Imi-Pops-Zr has promising application in the specific enrichment of phosphorylated peptides and exosomes in complex bio-samples.

Human Serum Albumin-enriched Clopidogrel Bisulfate Nanoparticle Alleviates Cerebral Ischemia-Reperfusion Injury in Rats.

PURPOSE: Cerebral ischemia-reperfusion (I/R) injury remains a leading cause of mobility and mortality among patients with ischemic stroke. This study aims to develop a human serum albumin (HSA)-enriched nanoparticle platform for solubilizing clopidogrel bisulfate (CLP) for intravenous administration, and to explore the protective effect of HSA-enriched nanoparticles loaded with CLP (CLP-ANPs) against cerebral I/R injury in transient middle cerebral artery occlusion (MCAO) rat model. METHODS: CLP-ANPs were synthesized via a modified nanoparticle albumin-bound technology, lyophilized, and then characterized by morphology, particle size, zeta potential, drug loading capacity, encapsulation efficiency, stability and in vitro release kinetics. In vivo pharmacokinetic studies were conducted using Sprague-Dawley (SD) rats. Also, an MCAO rat model was established to explore the therapeutic effect of CLP-ANPs on cerebral I/R injury. RESULTS: CLP-ANPs remained spherical particles with a layer of proteins forming protein corona. Lyophilized CLP-ANPs after dispersion displayed an average size of about 235.6 ± 6.6 nm (PDI = 0.16 ± 0.08) with a zeta potential of about - 13.5 ± 1.8 mV. CLP-ANPs achieved sustained release for up to 168 h in vitro. Next, a single injection of CLP-ANPs dose-dependently reversed the histopathological changes induced by cerebral I/R injury possibly via attenuating apoptosis and reducing oxidative damages in the brain tissues. CONCLUSIONS: CLP-ANPs represent a promising and translatable platform system for the management of cerebral I/R injury during ischemic stroke.

Organic-inorganic composite modifiers enhance restoration potential of Nerium oleander L. to lead-zinc tailing: application of phytoremediation.

Lead-zinc tailings are complex heavy metal solid wastes produced in the mining process. In this study, two kinds of organic-inorganic mixed improvers mushroom residue + calcium carbonate (M + C) and peat soil + calcium carbonate (N + C) were selected. Then, the effect of two improvers and a woody plant, Nerium oleander L., on the combined remediation of lead-zinc tailings was compared, respectively. The results showed that two combined improvers can slightly improve the pH of tailing, significantly increase the activity of phosphatase and catalase, effectively reduce the contents of DTPA-extractable Pb and Zn, and significantly improve the structure of tailing. However, the improvement effect of M + C was better than that of N + C on tailings' physical and chemical properties. Two improvers can reduce the enrichment and the stress degree of Pb and Zn on the N. oleander and increase the accumulation of Pb and Zn while promoting the growth of the N. oleander. The content of Pb and Zn showed the trend of root > stem > leaf under the two improvers, and the content of Zn was basically higher than that of Pb. To sum up, the combination of two modifiers and N. oleander has a good effect on the remediation of lead-zinc tailings, and the remediation effect of M + C was better than N + C.

Photocurable liquid crystal hydrogels with different chargeability and tunable viscoelasticity based on chitin whiskers.

We develop a kind of photocurable liquid crystal hydrogels with bone extracellular matrix (ECM)-like liquid crystal state and viscoelasticity, as well as different chargeability. First, positively charged chitin whiskers (CHWs) and negatively charged maleic anhydride chitin whiskers (mCHWs) were prepared, which further self-assemble to form chiral nematic liquid crystals under ultrasonic treatment, respectively. Subsequently, poly (ethylene glycol) diacrylate (PEGDA) and photo initiator were added, and then two kinds of liquid crystal hydrogels with bone ECM-like viscoelasticity and different chargeability were prepared under ultraviolet (UV) irradiation. Benefiting from the bone ECM-like liquid crystal state and viscoelasticity, the prepared liquid crystal hydrogels exhibit remarkable cell affinity and osteogenic ability. Moreover, the liquid crystal hydrogel with negatively charged mCHWs is more favorable for cell adhesion, spreading and osteogenic differentiation than that with positively charged CHWs. This work provides a promising strategy to prepare the hydrogels with bone ECM-like liquid crystal properties and viscoelasticity for bone repair.